Oh, how fun! Steam Deck is using Btrfs for its root filesystem, which... breaks audio in 32-bit games. libasound can't read ALSA config because of 64-bit inodes! Turns out it needs to be fixed to work with _FILE_OFFSET_BITS=64. In 2022! :D
I'm going to send a patch for alsa-lib when I catch some sleep. With that patch, all that's standing between Steam Deck and working audio in games like Day of the Tentacle or Full Throttle is installing `lib32-pipewire` \o/